Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Computerized tomography (CT) involves the imaging of the internal structure of a target object by collecting projection data in a single scan operation (“scan”). CT is widely used in the medical field to view the internal structure of selected portions of the human body. In an ideal imaging system, rays of radiation travel along respective straight-line transmission paths from the radiation source, through a target object, and then to respective pixel detectors of the imaging system to produce volume data (e.g., volumetric image) without artifacts.
However, in practice, volume data may contain image artifacts, such as streaking, noise, cupping, ringing, shadows, blurring, etc. For example, the image artifacts may be caused by errors in the projection data, such as data inconsistencies, missing data, geometrical uncertainties, superimposition in the projection space, various physical properties (e.g., scatter not covered by the reconstruction algorithm), etc. All of the foregoing leads to image degradation and affects, for example, subsequent diagnosis and treatment planning. It is therefore desirable to develop techniques that reduce image artifacts in the volume data by correcting the projection data.